Terminal lug



May 29, 1962 F. E. MYERS 3,037,132

TERMINAL LUG Filed April 8, 1959 2 Sheets-Sheet 1 INVENTOR. F54 /X f.44%595 Mf wt:

May 29, 1962 F. E. MYERS 3,037,182

TERMINAL LUG Filed April 8, 1959 2 Sheets-Sheet 2 United States Patent3,037,182 TERMINAL LUG Felix E. Myers, Haddon Heights, N.J., assignor toI-T-E Circuit Breaker Company, Philadelphia, Pa., a corporation ofPennsylvania Filed Apr. 8, 1959, Ser. No. 804,918 6 Claims. (Cl.339-149) My invention relates to a terminal lug structure which issimply and economically formed of a single conductive elementelectrically connected to the electrical circuit for which the terminalis adapted, and a single non-conductive clamping means for clamping anelectrical wire to the conductive terminal member.

In the past, terminal lugs have been formed generally of a conductivemember electrically connected to the circuit for which the terminal isadapted, and a clamping means which also includes a conductive member toclamp the wire in the lug. This requires electrical current to passthrough two intermediate electrical contacts at the terminal lug, andalso requires a relatively complex and expensive structure, Whereas alug should be as simple and inexpensive as possible while beingconsistent with highly reliable characteristics.

In the lug of the present invention, an electrical conductor isconnected to the electrical system, and in a preferred embodiment iscarried in a housing which is not necessarily conductive. The housingcarries a screw member which directly clamps a wire to the conductivemember and against the non-conductive member.

In a second embodiment of my invention, and still being consistent withthe use of a single conductive member, the conductive member itself maysupport a nonconductive fastening means for connecting a wire directlyto the conductive member.

Accordingly, the primary object of my invention is to provide a novelterminal lug.

Another object of my invention is to provide a novel terminal lug whichrequires only a single conductive element.

A further object of my invention is to provide a terminal lug of greatsimplicity wherein a wire is directly clamped to a conductive member.

Another object of my invention is to provide a highly reliable andinexpensive terminal lug structure.

These and other objects of my invention will become apparent from thefollowing description when taken in connection with the drawings, inwhich:

FIGURE 1 shows a first embodiment of my novel lug construction inconnection with a molded case circuit breaker.

FIGURE la shows a side view of the molded housing portion of the circuitbreaker of FIGURE 1 which receives my novel lug construction.

FIGURE 2 shows a side view of FIGURE 1 when looking from right to left.

FIGURE 3 shows the conductive terminal tongue of my novel lugconstruction in a side plan view.

FIGURE 4 is a front view of the lug of FIGURE 3 when seen looking fromthe right to the left in FIG- URE 3.

FIGURE 5 is a top view of the lug of FIGURE 3.

FIGURE 6 is a top view of the terminal collar or support means whichsupports the tongue of FIGURES 3 through 5.

FIGURE 7 is a side view of the collar of FIGURE 6 when looking fromright to left in FIGURE 6.

FIGURE 8 is a side view of the collar of FIGURE 7.

However, it will be obvious to those skilled in the art that the lug maybe used in any electrical application.

In FIGURE 1, the circuit breaker is generally comprised of a stab-typeline terminal 20 which is connected to a stationary contact 22. Amoveable contact and contact arm 24 then moves into and out ofengagement with stationary contact 22 by virtue of the operatingmechanism generally seen at numeral 26. The contact and contact arm 24is then connected to a bimetal 28 over the pigtail 30, and the upperportion of 'bimetal 28 is connected to a pigtail 32. The pigtail 32 isthen connected to the tongue portion 34 of my novel terminal lug, aswill be described more fully hereinafter, by means of welding or anyother desired type of electrical connection.

Further details of the circuit breaker construction are not givenherein, since they are fully described in U.S. application Serial No.807,885, now US. Patent 2,996,589 issued Aug. 15, 1961, co-entitledPivoted Bimetal in the name of Felix E. Myers, and assigned to theassignee of the instant application, which is here incorporated as partof the instant application.

The terminal lug forming the load terminal of the circuit breaker ofFIGURE 1 is comprised of the aforementioned tongue 34 and a collar 36which is a U-shaped stamping which is not necessarily of conductivematerial. Tongue 34 is best seen in FIGURES 3, 4 and 5 and is comprisedof a V-shaped conductive member. One portion of the leg of the V is cutaway at the left portion of the V-shaped member of FIGURES 3 and 5 atnumeral 38. The opposite leg of the extending V-shaped member isdownwardly bent, as at numeral 40, to form a fiat surface with which thelegs of the V intersect in a symmetric manner. This is the portion whichextends into the circuit breaker. The bottom portion of the V is furtherprovided with two crimps 42 and 44 which cause the crease of the V tohave projections 46 and 48 respectively which, as will be seenhereinafter, serve as means for securely bonding a load conductorconnected to the lug.

The collar of FIGURES 1 and 2 is seen in detail in FIGURES 6, 7 and 8 ascomprising a U-shaped member which is not necessarily of conductivematerial and is formed with a circular flange portion 50 at the bottomof the U which has internal threads to receive a clamping screw 52, asseen in FIGURES l and 2.

The side legs of collar 36 contain apertures such as aperture 54 ofFIGURE 8 wherein the bottom portion of the apeiture is V-shaped tocooperate with the bottom surface of tongue 34 of FIGURES 3, 4 and 5.The upper portion of aperture 54 is large enough so: that the tongue aswell as a load conductor to be connected to the circuit breaker ofFIGURE 1 may be received in aperture 54 with the load conductorthereafter being driven into high pressure contact with tongue 34 byclamping screw 52.

The manner in which the unit is assembled is understood by reference toFIGURES 1, 1a and 3 through 8. The housing of the circuit breaker ofFIGURE 1a is formed with a depressed molding portion 56 which issubstantially U-shaped to cooperate with the U-shaped cross-section ofcollar 36. Collar 36 will, therefore, fit directly into this moldingdepression to be supported thereby and in a fixed position with respectto the circuit breaker.

Before inserting the collar 36 into the molding. the tongue 34 is placedinto the opposing slots 54 in each leg of collar 36. The depth ofpenetration of tongue 34 into the collar is guided by the beginning ofthe bent portion 40 of the aforementioned leg of the V at the areaidentified by numeral 58 in FIGURES 3 and 5, since this portion of the Vwill fall outside of the V-shaped aperture 54 and prevent furtherentrance of the tongue 34 into collar 36. Preferably, this downwardlybent portion 40 will be so controlled that the end of tongue 34 will .besubstantially flush with the opposite wall of collar 36, as illustratedin FIGURE 1.

The unit soassembled is then placed in the molding of 3 the circuitbreaker so that the U-shaped collar 36 fits into molding depression 56of FIGURE 1a. The shoulder portion 60 of tongue 34 will then bearagainst molding pro ection 62 of FIGURE In so that a rearward motion oftongue 34 is prevented.

'Ijhe cover of the circuit breaker, which may contain a sim1lar slot 56for receiving U-shaped member 36 is then placed in position so that thecomplete unit is rigidly maintained within the circuit breaker.

It is to be noted that prior to the assembly, the rear- Wardly extendingflattened portion of the V-shaped tongue 34 will have been secured topigtail 32 as by welding or brazing or any other desired method,

In order to now secure a load conductor to the terminal lug, it will beobvious that the load conductor is inserted in aperture 54 and above thetongue 34, as seen in FIGURE 2, and the clamping screw 52 is thenthreaded downwardly so as to drive the load conductor into rigid highpressure contact engagement with tongue 34.

In order to secure a mechanically rigid connection, the position ofscrew 52 is between the two projecting portions 46 and 48 of tongue 34of FIGURE 5 so that these protrusions will tightly grip the loadconductor.

In the foregoing, I have described my invention only in connection withpreferred embodiments thereof. Many variations and modifications of theprinciples of my invention within the scope of the description hereinare obvious. Accordingly, I prefer to be bound not by the specificdisclosure herein but only by the appended claims.

I claim:

1. A terminal lug; said terminal lug including a conductive memberconnectible to the equipment associated with said terminal lug; saidterminal lug including means for receiving an electrical conductor and aclamping means; said clamping means being positioned to directly clampan electrical conductor to said conductive member; said clamping meansbeing a member Whose resistivity is materially greater than theresistivity of said conductive member; said conductive member having aV-shaped cross-section extending from a first end of said conductivemember to a point adjacent the opposite end, said opposite end beingsubstantially fiat and coplanar with the apex of the V-shaped portion;said clamping means comprising a U-shaped collar having partiallyV-shaped apertures in each leg for receiving the V-shaped portion ofsaid conductive member; the bottom of said U-shaped collar receiving athreaded member with an electrical conductor being insertable in one ofsaid aperturcs and between said conductive member and said threadedmember.

2. A terminal lug; said terminal lug including a conductive memberconnectible to the equipment associated with said terminal lug; saidterminal lug including means for receiving an electrical conductor and aclamping means; said clamping means being positioned to directly clampan electrical conductor to said conductive memher; said clamping meansbeing a member whose resistivity is materially greater than theresistivity of said conductive member; said conductive member having aV-shaped cross-section extending from a first end of said conductivemember to a point adjacent the opposite end, said opposite end beingsubstantially fiat and coplanar with the apex of the V-shaped portion;said clamping means comprising a U-shaped collar having partiallyV-shaped apertures in each leg for receiving the V-shaped portion ofsaid conductive member; the bottom of said U-shaped collar receiving athreaded member with an electrical conductor being insertable in one ofsaid apertures and between said conductive member and said threadedmember; said U-shaped collar being rigidly connected to said equipmentassociated with said terminal lug.

3. A terminal lug; said terminal lug comprising a tongue of conductivematerial and a collar of material having a resistivity substantiallygreater than the resistivity of said conductive material; said tongue ofconductive material being electrically connected to the electricalequipment associated with said terminal lug; said tongue being anelongated member having a first portion of V-shaped cross-section;extending from one end of said tongue to a point adjacent the oppositeend the remaining portion of said tongue being substantially flat; saidcollar having a U-shaped cross-section; each of the legs of saidU-shaped member having opposing partially V-shaped apertures therein;the bottom portion of said U-shaped member receiving a clamping screw;said tongue being positioned through said opposing apertures of saidU-shaped member and having a surface forming the inside of said V-shapeopposing said clamping screw; said flat remaining portion being adaptedto position said tongue with respect to said collar.

4. A terminal lug; said terminal lug comprising a tongue of conductivematerial and a collar of material having a resistivity substantiallygreater than the resistivity of said conductive material; said tongue ofconductive material being electrically connected to the electricalequipment associated with said terminal lug; said tongue being anelongated member having a first portion of V-shaped cross-sectionextending from one end of said tongue to a point adjacent the oppositeend of said tongue; said collar having a U-shaped cross-section; each ofthe legs of said U-shaped member having opposing partially V-shapedapertures therein; the bottom portion of said U-sha ed member receivinga clamping screw; said tongue being positioned through said opposingapertures of said U-shaped member and having a surface forming theinside of said V-shape opposing said clamping screw; said tongue havinga first and second stop means; said first stop means abutting a portionof said U-shaped member to prevent motion of said tongue in a firstdirection along the axis of said tongue; said second stop meansreceiving a portion of the electrical equip ment associated with saidlug to prevent motion of said tongue in a direction opposite to saidfirst direction; said tongue also having a second portion offset fromsaid first portion; said first and said second stop means both beinglocated at the junction between said first and said second portions.

5. A terminal lug; said terminal lug comprising a tongue of conductivematerial and a. collar of material having a resistivity substantiallygreater than the resistivity of said conductive material; said tongue ofconductive material being electrically connected to the electricalequipment associated with said terminal lug; said tongue being anelongated member having a first portion of J-shaped cross-sectionextending from one end of said tongue to a point adjacent the oppositeend of said tongue; said collar having a U-shaped cross-section; each ofthe legs of said U-shaped member having opposing apertures therein; thebottom portion of said U-shaped member receiving a clamping screw; saidtongue being positioned through said opposing apertures of said U-shapedmember and having a surface forming the inside of said V-shape opposingsaid clamping screw; said tongue having a first and second stop means;said first stop means abutting a portion of said U-shaped member toprevent motion of said tongue in a first direction along the axis ofsaid tongue; said second stop means receiving a portion of theelectrical equipment associated with said lug to prevent motion of saidtongue in a direction opposite to said first direction; the lowerportion of said opposing apertures having a V -shape to cooperate withthe outer portion of said V-shaped tongue to prevent motion of saidtongue in a direction perpendicular to the axis of said tongue; saidtongue also having a second portion offset from said first portion; saidfirst and said second stop means both being located at the junctionbetween said first and said second portions.

6. A terminal lug; said terminal lug comprising a tongue of conductivematerial and a collar of material having a resistivity substantiallygreater than the resistivity of said conductive material; said tongue ofconductive material being electrically connected to the electricalequipment associated with said terminal lug; said tongue being anelongated member having a first portion of V-shaped cross-sectionextending from one end of said tongue to a point adjacent the oppositeend of said tongue; said collar having a U-shaped cross-section; each ofthe legs of said U-shaped member having opposing apertures therein; thebottom portion of said U-shaped member receiving a clamping screw; saidtongue being positioned through said opposing apertures of said U-shapedmember and having a surface forming the inside of said V-shape opposingsaid clamping screw; said tongue having a first and second stop means;said first stop means abutting a portion of said U-shaped member toprevent motion of said tongue in a first direction along the axis ofsaid tongue; said second stop means receiving a portion of theelectrical equipment associated with said lug to prevent motion of saidtongue in a direction opposite to said first direction; said tongue alsohaving a second portion offset from said first portion; said first andsaid second stop means both being located at the junction between saidfirst and said second portions; the lower portion of said opposingapertures having a V-shape to cooperate with the outer portion of saidV-shaped tongue to prevent motion of said tongue in a directionperpendicular to the axis of said tongue; the bottom of said V-shapedtongue portion including a first and second projection aligned with saidclamping screw to permit rigid clamping of an electrical conductor tothe bottom of said V-shaped tongue.

References Cited in the file of this patent UNITED STATES PATENTS2,117,725 Johnson May 17, 1938 2,232,857 Jackson Feb. ,125, 19412,381,331 Ayers Aug. 7, 1945 2,657,370 Hobson Oct. 27, 1953 2,713,672Allen July 19, 1955 2,746,025 Radack May 15, 1956 2,774,953 Trier Dec.18, 1956 2,907,977 Daley Oct. 6, 1959 FOREIGN PATENTS 71,270 Norway June25, 1945 726,299 Germany Oct. 12, 1942

